JP2007025686A - Optical sheet, backlight assembly having the same and display device having the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical sheet capable of improving assembling processibility and enhancing the efficiency of light, and also to provide a backlight assembly having the optical sheet, and a display device having the optical sheet. <P>SOLUTION: The optical sheet includes a diffusion layer 420, a brightness enhancement layer 410 and a reflecting pattern layers 430, 440, 450. The diffusion layer 420 diffuses light and the brightness enhancement layer 410 is located on the surface side of the diffusion layer 420. The reflecting pattern layer is formed on the second region between the brightness enhancement layer 410 and the diffusion layer 420, and includes a reflective member which maintains a prescribed interval between the diffusion layer 420 and the brightness enhancement layer 410 and a gap 450 formed on the first region between the diffusion layer 420 and the brightness enhancement layer 410. Accordingly, the diffusion layer 420 is integrally formed with the brightness enhancement layer 410 to facilitate the assembling and the loss of light can be prevented by virtue of a gap 450 formed by the reflecting member 430. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an optical sheet, a backlight assembly having the optical sheet, and a display device having the optical sheet. More specifically, the present invention relates to an optical sheet capable of improving light efficiency and slimming, a backlight assembly having the optical sheet, and a display device having the optical sheet.

Recently, display devices that display images are rapidly developing according to their uses and types, and among various types of display devices, liquid crystal display devices that are superior in terms of performance and function are widely used. .
The liquid crystal display device is one of flat display devices widely used at present, and includes a liquid crystal display panel (Liquid Crystal) composed of two substrates on which electrodes are formed and a liquid crystal layer injected therebetween. display panel (hereinafter referred to as LCD panel). The liquid crystal display device displays an image by adjusting the amount of transmitted light by applying a voltage to the electrodes of the liquid crystal display panel to rearrange the liquid crystal molecules in the liquid crystal layer.

  Since such a liquid crystal display device displays an image using an LCD panel that adjusts the amount of light coming from the outside, in order to form the image on the LCD panel, the LCD panel is irradiated with light. A separate light source, i.e. a backlight assembly, is required.

The backlight assembly includes a reflective sheet that is stacked on a storage container and transmits light to the LCD panel, a diffusion plate, a plurality of optical sheets, and a lamp assembly that is disposed under the diffusion plate and generates the light. ,including. The optical sheet includes a diffusion sheet having a thin film structure and a prism sheet.
Here, there is a problem that the assembly process of the optical sheet having a thin film structure is further complicated by increasing the size of the plurality of optical sheets on the diffusion plate.

In addition, since the assembly process of the optical sheet is complicated, the manufacturing cost of the backlight assembly increases.
An object of this invention is to provide the optical sheet for improving the efficiency of light while improving assembly property.
Another object of the present invention is to provide a backlight assembly having the optical sheet.

  Another object of the present invention is to provide a display device having the backlight assembly.

In order to solve the above problems, the present invention 1 provides an optical sheet including the following components.
A diffusion layer that diffuses light from the light source,
A light collecting layer disposed on the opposite side of the light source across the diffusion layer,
A reflecting member that is formed on the condensing layer, maintains a predetermined interval between the diffusion layer and the condensing layer, and forms a gap having the interval between the condensing layer and the diffusion layer.

The present invention 2 provides the optical sheet according to the first invention, wherein a plurality of irregularities are formed in the diffusion layer.
The present invention 3 provides the optical sheet according to the first invention, wherein the light collecting layer includes a base film and a plurality of lenses formed on the base film.
Invention 4 is an optical sheet according to Invention 3, wherein each of the plurality of lenses extends along the longitudinal direction of the light source, is adjacent to each other, and has a semicircular cross section in a plane perpendicular to the longitudinal direction. provide.

According to a fifth aspect of the present invention, in the third aspect, each of the plurality of lenses extends along the longitudinal direction of the light source, is adjacent to each other, and has a cross-section in a plane perpendicular to the longitudinal direction. An optical sheet having a shape is provided.
The present invention 6 provides the optical sheet according to the invention 3, wherein each of the plurality of lenses extends along the longitudinal direction of the light source, is adjacent to each other, and has a trapezoidal cross section in a plane perpendicular to the longitudinal direction. To do.

A seventh aspect of the present invention provides the optical sheet according to the third aspect, wherein the reflecting member is formed to extend in a longitudinal direction of the lamp at a position corresponding to a boundary region between the plurality of lenses.
The present invention 8 provides the optical sheet according to the first invention, wherein the reflecting member is integrally formed on a light source side surface of the condensing layer.

The present invention 9 provides the optical sheet according to the first invention, wherein the reflecting member is any one of titanium dioxide (TiO ₂ ), silver (Ag), and white polyethylene terephthalate (PET).
A tenth aspect of the present invention provides the optical sheet according to the first aspect of the present invention, further comprising an adhesive pattern that is formed between the reflective member and the diffusion layer and adheres the diffusion layer to the reflective member.

The present invention 11 is a backlight assembly used in a display device,
A light source that generates light;
A transparent plate disposed on the display surface side of the light source and formed of a transparent material;
And a backlight assembly including an optical sheet disposed closer to the display surface than the transparent plate. Here, the optical sheet has the following components.
A diffusion layer for diffusing light from the transparent plate;
A light collecting layer disposed on the opposite side of the light source across the diffusion layer,
A reflective pattern layer including a reflective member that maintains a gap between the diffusion layer and the light collection layer and forms a gap between the diffusion layer and the light collection layer.

A twelfth aspect of the present invention provides the backlight assembly according to the eleventh aspect, wherein the light collecting layer includes a base film and a plurality of lenses formed on the base film.
In a thirteenth aspect of the present invention based on the twelfth aspect, the condensing layer includes a first region and a second region in contact with the first region and having a lens thickness smaller than a thickness of the lens located in the first region. A backlight assembly is provided. Here, the reflection member is formed to extend in the longitudinal direction of the light source at a position corresponding to the second region on the light collecting layer.

A fourteenth aspect of the present invention provides the backlight assembly according to the eleventh aspect, wherein the reflection member is integrally formed on a surface of the light collecting layer on the light source side.
According to a fifteenth aspect of the present invention, there is provided the backlight assembly according to the eleventh aspect, further including an adhesive pattern formed between the reflective member and the diffusing layer to adhere the diffusing layer to the reflective member.

The present invention 16 provides a display device including a display unit for displaying an image and a backlight assembly. Here, the backlight assembly includes the following components.
A light source that generates light for displaying the image;
A transparent plate that is disposed closer to the display surface than the light source and is formed of a transparent material;
-An optical sheet disposed on the display surface side of the transparent plate.

The optical sheet has the following components.
A diffusion layer for diffusing light from the transparent plate;
A light collecting layer disposed on the opposite side of the light source across the diffusion layer,
A reflective pattern layer including a reflective member that maintains a gap between the diffusion layer and the light collection layer and forms a gap between the diffusion layer and the light collection layer.

  If the present invention is used, the diffusion layer and the light condensing layer are integrally formed, so that assembly is facilitated. In addition, since the gap between the two layers is formed by the reflecting member, the loss of light can be reduced.

≪Backlight assembly≫
<Overall configuration>
Hereinafter, a backlight assembly according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is an exploded perspective view illustrating a backlight assembly according to an embodiment of the present invention. FIG. 2 is a side view of the backlight assembly shown in FIG. 1 as viewed from one direction.

As shown in FIGS. 1 and 2, the backlight assembly 100 according to the present invention includes a lamp unit 200, a diffusion plate 300, an optical sheet 400, a reflection plate 500, and a storage container 600.
The lamp unit 200 includes a plurality of lamps 210 arranged in parallel to generate light and a lamp holder 220 for fixing both ends of the lamps 210. The lamp 210 is a cold cathode fluorescent lamp (CCFL) having a rod shape. A hot electrode (not shown) for applying a high voltage and a cold electrode (not shown) for providing a low voltage are connected to both ends of the lamp 210, respectively. The lamp holders 220 are installed to cover the hot electrode and the cold electrode of the lamp 210, respectively.

  The diffusion plate 300 is formed on the upper side of the lamp unit 200 in the drawing, that is, on the front side, and diffuses the light from the lamp unit 200. Further, the diffusion plate 300 supports the optical sheet 400 positioned on the upper side in the drawing, that is, on the front side. The diffusion plate 300 is made of a transparent material. Here, the diffusion plate 300 can be formed of polycarbonate (PC) or polymethyl methacrylate (PMMA). By forming the diffusing plate 300 from a transparent material, loss of light from the lamp unit 200 can be reduced.

  The optical sheet 400 includes a condensing layer 410 having a diffusing and condensing function, and a diffusion layer 420 integrally formed with the condensing layer 410 on the lower side of the condensing layer 410 in the drawing, that is, on the back side. The condensing layer 410 is located on the opposite side of the lamp unit 200 with the diffusion layer 420 interposed therebetween. In addition, the optical sheet 400 further includes a reflective member 430 and an adhesive pattern 440. Here, a gap 450 (see FIG. 3) is formed between the condensing layer 410 and the diffusion layer 420 by the reflecting member 430 and the adhesive pattern 440. The gap 450 includes an air layer, a vacuum layer, an inert gas layer, and the like. The reflective member 430, the adhesive pattern 440, and the gap 450 form a reflective pattern layer.

The reflection plate 500 is formed on the lower side of the lamp unit 200 in the drawing, that is, the back side, reflects light leaking from the lamp unit 200 and enters the diffusion plate 300.
The storage container 600 is formed on the lower side of the reflecting plate 500 in the drawing, that is, on the back side, and forms a storage space by a bottom portion and a side portion extending from an end portion of the bottom plate portion. The optical sheet 400, the diffusion plate 300, and the lamp unit 200 are sequentially stored in the storage space.

<Optical sheet>
(1) Configuration of Optical Sheet FIG. 3 is a detailed cross-sectional view of the optical sheet 400 shown in FIGS. 1 and 2. The optical sheet 400 includes a light collecting layer 410, a diffusion layer 420, a reflective member 430, and an adhesive pattern 440.
The condensing layer 410 includes, for example, a base film 412 made of polycarbonate (PC) and a plurality of lenses 414 formed on the base film 412. The plurality of lenses 414 extend in the longitudinal direction of the lamp 210. The cross-sectional shape of the lens 414 in a plane perpendicular to the longitudinal direction of the lamp 210 is a semicircular shape.

The condensing layer 410 is divided into a first region A1 corresponding to each of the plurality of lenses 414 and a second region A2 corresponding to the boundary region of the adjacent lenses 414. In the first region A1, the height of the lens 414 is relatively higher than that of the second region A2.
The condensing layer 410 not only collects the light provided through the diffusion plate 300 but also diffuses it. That is, since a plurality of images of the lamp 210 are formed by the plurality of lenses 414, generation of bright lines can be prevented. Therefore, the separation distance from the lamp 210 can be reduced, and the backlight assembly can be slimmed.

  More specifically, since the condensing layer 410 includes a plurality of lenses 414, a plurality of lamp images are formed. That is, the condensing layer 410 does not simply collect light but mixes light. In general, bright lines are more likely to be generated as the distance between the lamp and the optical sheet is shorter. However, if light is mixed better by the condensing layer 410, generation of bright lines can be suppressed. Accordingly, the lamp 210 and the optical sheet 400 can be brought closer to each other, and the backlight assembly can be slimmed.

The diffusion layer 420 is bonded to the reflective member 430 by an adhesive pattern 440 formed on the reflective member 430. As a result, the light collecting layer 410, the reflecting member 430, and the diffusion layer 420 are integrally formed.
A plurality of irregularities 425 for diffusing light from the plurality of lamps 210 are formed on the back surface of the diffusion layer 420. The plurality of irregularities 425 are formed to protrude from the back surface of the diffusion layer 420 to a predetermined height. Here, the plurality of irregularities 425 are formed by a sandblasting method in which, for example, sand is jetted out. Further, the diffusion layer 420 does not include diffusion beads that are particles having a refractive index different from that of the remaining portion of the diffusion layer 420 inside.

  When light is diffused by the diffusion beads, light having an output angle exceeding ± 42 ° that can affect light loss relatively increases in the output light from the diffusion layer 420. The emission angle is an angle of the emitted light with respect to a direction perpendicular to the light emitting surface. On the other hand, according to the present embodiment example in which the diffusion beads 420 are not present in the diffusion layer 420, there is no change in the light emission angle by the diffusion beads, and amorphous diffusion is performed by the plurality of irregularities 425. The light having an emission angle in the range exceeding 1 is relatively reduced as compared with the case where there are diffusion beads.

The reflecting member 430 is integrally formed on the lower surface of the light collecting layer 410 in the drawing. The reflection member 430 is disposed at a position corresponding to the second region A2 of the light condensing layer 410, extends in the longitudinal direction of the lamp 210, and has a predetermined height. Here, the reflecting member 430 is preferably formed using any one of titanium dioxide (TiO ₂ ), silver (Ag), and white polyethylene terephthalate (PET).

  The gap 450 is formed in the second region between the condensing layer 410 and the diffusion layer 420 by the reflective member 430 and the adhesive pattern 440 formed in the first region. That is, a gap 450 corresponding to the sum of the heights of the reflective member 430 and the adhesive pattern 440 exists in the second region between the light condensing layer 410 and the diffusion layer 420. The gap is filled with a gas such as air. The gap 450 is divided into a plurality of sections by a reflective member 430 and an adhesive pattern 440.

  By forming the gap 450 between the light condensing layer 410 and the diffusion layer 420, the emission angle when the light diffused in the diffusion layer 420 is emitted from the diffusion layer 420 can be adjusted. That is, out of the light diffused by the diffusion layer 420, light having an emission angle of about ± 42 ° or less collected by the light condensing layer 410 is passed through the gap 450 to be emitted from the diffusion layer 420 to the gap 450. The light emission angle can be reduced. As a result, the loss of light incident on the light collecting layer 410 from the diffusion layer 420 can be reduced. When there is no gap 450, light having an emission angle of about ± 42 ° or more out of the light that has passed through the diffusion layer 420 is lost without passing through the light condensing layer 410. However, if the gap 450 is provided, the gap 450 serves as a bump before the diffused light enters the light collecting layer 410. That is, when light randomly spread by the diffusion layer 420 enters the light collection layer 410 from the gap 450, it is refracted in the direction perpendicular to the surface, and damage is reduced.

4 and 5 are sectional views of an optical sheet according to another embodiment of the present invention. In the present embodiment, the remaining components excluding the cross-sectional shape of the lens are the same as those in the embodiment shown in FIG.
The cross-sectional shape perpendicular to the longitudinal direction of the lamp 210 of the plurality of lenses 414 in FIG. 4 has a prism shape with rounded vertices.

The cross-sectional shape perpendicular to the longitudinal direction of the lamp 210 of the plurality of lenses 414 in FIG. 5 is generally trapezoidal.
(2) Manufacturing Method of Optical Sheet FIGS. 6 to 8 are cross-sectional views showing manufacturing steps of the reflecting member shown in FIG.
As shown in FIG. 6, a reflective material 700 for forming a reflective member is formed on the upper surface of the condensing layer 410 in the drawing, that is, the rear surface. The reflective material 700 may be formed using titanium dioxide, silver, white PET, or the like. The condensing layer 410 includes a plurality of lenses 414 formed on the lower surface in the drawing, that is, the front surface.

Thereafter, a photosensitive photoresist 710 is formed on the upper surface of the reflective material 700 in FIG. The photoresist 710 has a property of being cured by ultraviolet (UV) light.
After forming the photoresist 710, as shown in FIG. 7, the ultraviolet light is irradiated from the lower side of the condensing layer 410 in the drawing, that is, from the front side. The photoresist 710 is cured by the ultraviolet light. Here, the condensing layer 410 is near the boundary between the first region A1 having a relatively large height, that is, the thickness of the plurality of lenses 414, and the lens 414, and the height or thickness of the lens 414 is smaller than that of the first region. Then, it can be divided into a relatively low second region A2.

Accordingly, the photoresist 710 has different degrees of curing in the region corresponding to the first region A1 and the region corresponding to the second region A2. That is, the photoresist 710 has a relatively high degree of curing in the region corresponding to the second region A2 as compared with the first region A1.
Thereafter, the reflective material 700 is patterned using the photoresist 710 cured by the ultraviolet light. Therefore, the reflective material 700 is removed in the region corresponding to the first region A1, and the reflective material 700 remains only in the region corresponding to the second region A2. Thereby, the reflection member 430 is formed in a region corresponding to the second region A2.

  FIG. 8 shows a state where an adhesive pattern 440 is formed on the reflective member 430. For example, an adhesive material coated on a transfer substrate (not shown) or a transfer roller (not shown) can be printed on the reflective member 430 to form the adhesive pattern 440. Alternatively, the adhesive pattern 440 may be formed by directly printing an adhesive material on the reflective member 430 through a mask. The adhesive pattern 440 can be formed by various methods. Various adhesive materials such as an organic adhesive, an inorganic adhesive, a thermosetting material, and a photocuring material can be used as the material for the adhesive pattern.

(3) Action of Gap FIG. 9 is a view showing the principle of adjusting the light emission angle by the gap shown in FIG.
As shown in FIG. 9, the first light L <b> 1 emitted from the lamp 210 is diffused through the diffusion plate 300 and then emitted to the diffusion layer 420. Thereafter, the first light L <b> 1 is diffused again from the diffusion layer 420 and is emitted to the gap 450. Here, the second light L2 diffused by the diffusion layer 420 and emitted to the gap 450 includes light having an emission angle exceeding about ± 42 ° indicated by the dotted line.

  The second light L <b> 2 passes through the gap 450 and enters the light collecting layer 410. Here, most of the third light L3 that passes through the gap 450 and enters the light condensing layer 410 has an emission angle within about ± 42 °. That is, of the second light L2, light having an emission angle exceeding about ± 42 ° is refracted through the gap 450, and is emitted within about ± 42 ° when emitted from the diffusion layer 420 toward the condensing layer 410. Comes with horns.

Therefore, a large amount of the third light L3 is condensed by the condensing layer 410. As a result, optical loss can be reduced.
Referring to FIG. 3 again, the reflecting member 430 reflects the light that is not refracted by the condensing layer 410 but is refracted downward, and re-enters the condensing layer 410. Therefore, the light efficiency can be further improved.

<Effect of backlight assembly>
As described above, the present invention can reduce light loss by the transparent diffusion plate 300. Generation of bright lines of the lamp 210 by the transparent diffusion plate 300 can be prevented by the condensing layer 410 having a plurality of convex lenses 414. Accordingly, since the separation distance between the lamp 210 for removing the bright line and the optical sheet 400 can be reduced, the backlight assembly can be slimmed.

  Further, by adjusting the emission angle of the diffused light from the diffusion plate 300 to a range within about ± 42 ° by the gap 450 formed between the light condensing layer 410 and the diffusion layer 420, Light loss can be suppressed. By not including diffusion beads in the diffusion layer 420, light having an emission angle exceeding about ± 42 ° among the diffusion light from the diffusion plate 300 is reduced. Thereby, the light loss in the condensing layer 410 can be suppressed, and the light efficiency of the backlight assembly can be improved.

≪Liquid crystal display device≫
FIG. 10 is an exploded perspective view showing a liquid crystal display device according to the present invention. In this embodiment, since the backlight assembly has the same configuration as that shown in FIGS. 1 to 3, the same reference numerals are used for the same configuration, and the detailed description thereof is omitted. To do.
Referring to FIG. 10, the liquid crystal display device according to the present invention includes the following components (a) to (c).
(a) a backlight assembly 100 for supplying light;
(b) Display unit 800 for displaying an image using light supplied from backlight assembly 100
(c) A top chassis 900 for fixing the display unit 800 to the backlight assembly 100.

The backlight assembly 100 includes the following components (a) to (e).
(a) Lamp unit 200 that generates light
(b) A diffusion plate 300 that is formed on the lamp unit 200 and diffuses light generated from the lamp unit 200.
(c) An optical sheet 400 formed on the diffusion plate 300 and improving the optical characteristics of the diffused light.
(d) A reflection plate 500 that is formed below the lamp unit 100 and reflects light leaked from the lamp unit 100 to the display unit 800 side.
(e) A storage container 600 that is formed below the reflection plate 500 and sequentially stores the lamp unit 200, the diffusion plate 300, and the optical sheet 400.

  The optical sheet 400 includes a light collecting layer 410, a diffusion layer 420, a reflective member 430, and an adhesive pattern 440. A gap 450 is formed between the condensing layer 410 and the diffusion layer 420 by the reflective member 430 and the adhesive pattern 440. By adjusting the range of the emission angle of light emitted from the diffusion layer 420 by the gap 450, light loss in the light condensing layer 410 can be reduced and the light efficiency of the liquid crystal display device can be improved.

Meanwhile, the display unit 800 includes a liquid crystal display panel 810 that displays an image, a source printed circuit board 820 that outputs a drive signal for driving the liquid crystal display panel 810, and a gate printed circuit board 830.
The liquid crystal display panel 810 includes a thin film transistor (hereinafter referred to as a TFT substrate) 812, a color filter substrate 814 coupled to face the TFT substrate 812, and a liquid crystal layer between the TFT substrate 812 and the color filter substrate 814. (Not shown).

The TFT substrate 812 is a transparent glass substrate on which TFTs (not shown) as switching elements are formed in a matrix form. A data line is connected to the source terminal of the TFT, and a gate line is connected to the gate terminal. In addition, a pixel electrode made of a transparent conductive material is connected to the drain terminal.
The color filter substrate 814 is spaced apart from the TFT substrate 812 at a predetermined interval and is disposed opposite to the TFT substrate 812. The color filter substrate 814 is a substrate on which RGB pixels, which are color pixels that express a predetermined color when light passes, are formed by a thin film process. A common electrode made of a transparent conductive material is formed on the entire surface of the color filter substrate 814.

  In the liquid crystal display panel 810 having such a configuration, when a power is applied to the gate terminal of the TFT and the TFT is turned on, an electric field is formed between the pixel electrode and the common electrode. This electric field changes the alignment of the liquid crystal between the TFT substrate 812 and the color filter substrate 814. The transmittance of the light supplied from the backlight assembly 100 is polarized by the change in the alignment of the liquid crystal, and an image having a desired gradation is obtained.

  The source printed circuit board 820 is connected to one end of the TFT substrate 812 through the data flexible circuit film 840. Further, the gate printed circuit board 830 is connected to the other end of the TFT substrate 812 through the gate flexible circuit film 850. The source printed circuit board 820 and the gate printed circuit board 830 generate and output a data driving signal and a gate driving signal for driving the liquid crystal display panel 810, respectively.

  The driving signals output from the source printed circuit board 820 and the gate printed circuit board 830 are input to the liquid crystal display panel 810 through the data flexible circuit film 840 and the gate flexible circuit film 850. For example, the data flexible circuit film 840 and the gate flexible circuit film 850 are formed of a tape carrier package (TCP) or a chip on film (COF).

  Here, each of the data flexible circuit film 840 and the gate flexible circuit film 850 may further include a data driving chip 860 and a gate driving chip 870. The data driving chip 860 controls the timing of the data driving signal in order to apply the data driving signal from the source printed circuit board 820 to the liquid crystal display panel 810 at an appropriate timing. The gate driving chip 870 controls the timing of the gate driving signal in order to apply the gate driving signal provided from the gate printed circuit board 830 to the liquid crystal display panel 810 at an appropriate timing.

  The data driving signal is a driving signal for outputting to the data line formed on the TFT substrate 812 and is applied to the data line through the data flexible circuit film 840. The gate driving signal is a driving signal for outputting a gate line formed on the TFT substrate 812, and is applied to the gate line via the gate flexible circuit film 850. For this, a conductive wiring (not shown) for connecting the data flexible circuit film 840 and the gate flexible circuit film 850 is formed on the TFT substrate 812.

  On the other hand, the display unit 800 is mounted from the upper side of the backlight assembly 100 in the drawing, that is, from the front side. Here, the liquid crystal display panel 810 is accommodated in the upper mold frame 950 and disposed on the backlight assembly 100. The source printed circuit board 820 is fixed to the back surface of the storage container 600 by bending the data flexible circuit film 840.

The top chassis 900 surrounds the edge of the liquid crystal display panel 810 housed in the backlight assembly 100 and is coupled to the housing container 600. The top chassis 900 prevents the liquid crystal display panel 810 from being damaged by an external impact, and prevents the liquid crystal display panel 810 from being detached from the storage container 600.
In the embodiments of the present invention, the liquid crystal display device is taken as an example, but the present invention can also be applied to other display devices having a diffusion plate for diffusing light.

<< Effect of the invention >>
In the present invention, the diffusion layer and the light collecting layer are integrally formed, and a gap is formed between the light collecting layer and the diffusion layer by the reflecting member formed between the light collecting layer and the diffusion layer. Since the diffusion layer and the light collecting layer are integrally formed, the assembling property can be improved and the manufacturing cost can be reduced. In addition, by adjusting the emission angle of the light emitted from the diffusion layer by the gap formed between the diffusion layer and the light collection layer, all light can be collected and diffused by the light collection layer. Can be reduced.

The formation of bright lines can be prevented by forming a plurality of lenses for condensing and diffusing light on the upper surface of the condensing sheet and forming a plurality of lamp images. In addition, the backlight assembly can be made slim by reducing the separation distance between the lamp and the condensing layer in order to prevent generation of bright lines.
By forming multiple irregularities for amorphous diffusion on the back of the diffusion layer without forming the beads that existed in the diffusion layer, the light with the emission angle lost in the condensing layer is made relative. Can be reduced.

By using a transparent diffusion plate, the loss of light provided from the lamp can be reduced.
As described above, the embodiments of the present invention have been described in detail. However, the present invention is not limited to these embodiments, and any person who has ordinary knowledge in the technical field to which the present invention belongs can be used without departing from the spirit and spirit of the present invention. The present invention can be modified or changed.

The present invention is an exploded perspective view showing a backlight assembly according to an embodiment. Sectional view seen along I-I 'shown in FIG. Sectional drawing which showed the optical sheet shown in FIG.1 and FIG.2 in detail Sectional drawing which shows the optical sheet by the other Example of this invention. Sectional drawing which shows the optical sheet by the other Example of this invention. Sectional drawing which shows the manufacturing process of the reflective member shown in FIG. 3 (formation of a reflective material) Sectional drawing which shows the manufacturing process of the reflective member shown in FIG. 3 (formation of a reflective member) Sectional drawing which shows the manufacturing process of the reflective member shown in FIG. 3 (formation of an adhesion pattern) Explanatory drawing which shows the adjustment principle of the light emission angle by the gap shown in FIG. 1 is an exploded perspective view showing a liquid crystal display device according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Backlight assembly 200 Lamp unit 300 Diffusing plate 400 Optical sheet 410 Condensing layer 420 Diffusion layer 430 Reflecting member 440 Adhesive pattern 450 Gap 500 Reflecting plate 600 Storage container

Claims (16)

A diffusion layer for diffusing light from the light source;
A light condensing layer disposed on the opposite side of the light source with the diffusion layer interposed therebetween;
A reflecting member formed on the light collecting layer, maintaining a predetermined distance between the diffusion layer and the light collecting layer, and forming a gap having the distance between the light collecting layer and the diffusion layer;
Optical sheet including   The optical sheet according to claim 1, wherein a plurality of irregularities are formed in the diffusion layer. The condensing layer is
A base film,
A plurality of lenses formed on the base film;
The optical sheet according to claim 1, comprising:   4. The optical sheet according to claim 3, wherein each of the plurality of lenses extends in the longitudinal direction of the light source, is adjacent to each other, and has a semicircular cross section in a plane perpendicular to the longitudinal direction.   4. The optical system according to claim 3, wherein each of the plurality of lenses extends along a longitudinal direction of the light source, is adjacent to each other, and has a cross section in a plane perpendicular to the longitudinal direction having a triangular shape with a rounded vertex. Sheet.   4. The optical sheet according to claim 3, wherein each of the plurality of lenses extends along the longitudinal direction of the light source, is adjacent to each other, and has a trapezoidal cross section in a plane perpendicular to the longitudinal direction.   The optical sheet according to claim 3, wherein the reflection member is formed to extend in a longitudinal direction of the lamp at a position corresponding to a boundary region between the plurality of lenses.   The optical sheet according to claim 1, wherein the reflecting member is integrally formed on a light source side surface of the light collecting layer. The optical sheet according to claim 1, wherein the reflection member is made of any one of titanium dioxide (TiO ₂ ), silver (Ag), and white polyethylene terephthalate (PET).   The optical sheet according to claim 1, further comprising an adhesive pattern that is formed between the reflective member and the diffusion layer and adheres the diffusion layer to the reflective member. A backlight assembly used in a display device,
A light source that generates light;
A transparent plate disposed on the display surface side of the light source and formed of a transparent material;
An optical sheet disposed closer to the display surface than the transparent plate,
The optical sheet is
A diffusion layer for diffusing light from the transparent plate;
A light condensing layer disposed on the opposite side of the light source with the diffusion layer interposed therebetween;
A backlight assembly comprising: a reflective pattern layer including a reflective member that maintains a gap between the diffusion layer and the light collection layer and forms a gap between the diffusion layer and the light collection layer. The condensing layer is
A base film,
A plurality of lenses formed on the base film;
The backlight assembly of claim 11 comprising: The condensing layer is composed of a first region and a second region that is in contact with the first region and has a lens thickness smaller than the thickness of the lens located in the first region,
The backlight assembly according to claim 12, wherein the reflecting member is formed to extend in a longitudinal direction of the light source at a position corresponding to the second region on the light collecting layer.   The backlight assembly according to claim 11, wherein the reflecting member is integrally formed on a surface of the light collecting layer on the light source side.   The backlight assembly of claim 11, further comprising an adhesive pattern formed between the reflective member and the diffusing layer to adhere the diffusing layer to the reflective member. A display unit for displaying an image, and a backlight assembly,
The backlight assembly includes:
A light source that generates light for displaying the image;
A transparent plate disposed on the display surface side of the light source and formed of a transparent material;
An optical sheet disposed closer to the display surface than the transparent plate,
The optical sheet is
A diffusion layer for diffusing light from the transparent plate;
A light condensing layer disposed on the opposite side of the light source with the diffusion layer interposed therebetween;
A display device comprising: a reflective pattern layer including a reflective member that maintains a gap between the diffusion layer and the light collection layer and forms a gap between the diffusion layer and the light collection layer.

Images